Return of Reckoning

hi there,
after playing for a while and can't connect to server anymore. when i select a character and hit play, the game starts loading and then suddenly kicks me back to desktop saying:

critical error
data file corrupted - please re-launche warhammer online

relaunching warhammer online doesn't get me any further


thanks for helping

anyone?
anything?
please?

Either re-download the RoR launcher or the client first and check, but I'd go straight to a quick client reinstall.